Ring grinding fixture



Sept. 6, 1949. R1 STENWALL 2,481,173

RING GRINDING FIXTURE Filed OOL. 20, 1947 2 Sheets-Sheet 1 t mvamon Inaam 51m-1ML TG. E.. Xgl

oRNgfs Sept. 6, 1949. R. STENWALL. v 2,481,173

RING GRINDING FIXTURE Filed Oct. 20, 1947 2 Sheets-Sheet 2 l \NvE.NToRl' 'Rosan STLNWALL.

. L" Q1-hw SL Patented Sept. 6, 1949.

RING GRINDING FIXTURE Robert Stenwall, Newaygo, Mich., assignor toMuskegon Piston RingCompany, Muskegon, Mich., a corporation of MichiganApplication October 20, 1947, Serial No. 780,971

6 Claims.

This invention relates to a simple, novel, but very practical andeiiective attachment for ring grinding 'machines of the type shown in myPatent #2,397,298 granted March 26, 1946.

In the structure of the aforesaid patent the grinding of rings, andparticularly piston rings at their outer curved surfaces, is veryeficiently attained. Machines designed and built for piston ringgrinding are capable of handling piston rings in substantially all ofthe diameter sizes, such as are used in internal combustion engines ofautomobiles. which may be packing rings, and others continuous ringswithout any partings therein, of smaller diameters than the smallestdiameter of automotive piston rings, which can not be effectively groundupon the machines which have been built for piston ring grinding inaccordance with the structure of my patent. Of course, other machinesdesigned for smaller diameter rings less than what in general is aboutthe smallest piston ring diameter, namely, 2% inches, could be built forsuch small ring grinding exclusively. This would necessitate the expenseof a complete machine and the cost of its occupying floor space in afactory, not only at times when it was in use, but at all other times.

The present invention is directed to a simple, easily connected andquite as readily disconnected attachment for the piston ring grindingmachines which have been built, and with such attachment, the otherrings of the smaller diameters wanted may be quite as accurately andeffectively ground when such attachment is used, as the larger diameterpiston rings are ground in the existing machines without the attachment.Many rings having a diameter of approximately one inch and varying indiameters between one inch and the minimum size of internal combustionengine piston rings, and usable for many purposes, are rapidly groundwith high quantity production with my invention.

It is an object and purpose of the present invention to provide a novel,practical and easily connected attachment for piston ring grindingmachines of the structure disclosed in the aforesaid patent, with whichthe numerous sizes and diameters of rings of the lesser diameterswanted, may be effectively ground with rapid, high quantity production.

An understanding of the invention may be had from the followingdescription, taken in connection with the accompanying drawings, inwhich,

Fig. l is a transverse vertical section through one of the piston ringgrinding machines made There are other rings, some of in accordance withPatent #2,397,298, and to which the novel atttachment of the presentinvention is connected, said attachment being vshown in elevation andtransverse section,

section of the structure Shown in Fig. 1,

Fig. 3 is a plan view, and

Fig. 4 is a fragmentary elevation of the shim attachment used when ringsof smaller diameter `are to be ground.

Like reference characters refer to like parts in the diierent figures ofthe drawings.

On a base plate I, spaced apart supporting posts 2 and 3 are secured,which are to carry the arbor on which a plurality of rings to he groundis mounted. At opposite sides of the posts, and `mounted upon the basein any suitable manner, are lower horizontal shafts 4 from which spacedarms 5 extend upwardly between the upper ends of which rubber coveredhorizontal rollers 6 are mounted. Bars 1 connect the arms 5 at each sideof the structure described and are connected by links 8 with rockingarms 9 for moving the rollers 6 inwardly and outwardly toward the arborI0, upon which a plurality of rings to be ground are held. Said arborsI0 at each end have bearings II which are to be received in blocks I2secured at the upper ends of the posts 2 and 3. The blocks I2 areprovided with concave recesses at their upper sides in which spacedhardened pins I3, as shown in Fig. v4, are located. The rings I 4, whichare to be ground, are of larger interior diameter than the diameter ofthe arbor IEI over which they are located and from which they aresuspended.

The structure thus far described is illustrative of the environment ofmy invention and is substantially identical with that disclosed in myrearlier patent. With the rings I4 sufficiently large in diameter, andusually at least 2'1/8 inches in diameter or more, the rollers ii may beswung inwardly toward each other to bear on opposite ,sides of the ringsabove the center of the arbor. The rollers are driven so that the ringsare turned about their centers in the operation of the machine. Suchdriving mechanism forms no part of the present invention and is notshown or described, but it is fully shown and described in my earlierpatent which has been mentioned.

In the present invention a bar I5 is detachably connected at the innerside of each of the posts 2 and 3 by bolts or screws. Horizontal shaftsI6 extend between the end portions of the bars I5. Arms I'I are securelyconnected to said shafts I6 at the ends thereof and extend upwardly.Rollers I8 are mounted on and extend between the upper ends of the armsI'I, one roller I8 at each side of the arbor I0. The rollers I8 haveaxes of rotation above the rotative axes of the rollers 6 and arebetween said rollers 9 and the rings I4 which are to be ground.

From each of the shafts I6 an arm I9 extends downwardly. 'The lower endsof the two arms I9 are connected by a coiled tension spring 29 as shown,the effect of which is to tend to move the rollers I8 outwardly and thusmaintain them against the driving rollers 6.

The grinding wheel 2I, having a horizontal under-grinding face, isdisposed the same as in my issued patent, with its lower face in a planesuch that the turning rings I4 are brought to said grinding face and theplurality of rings on the arbor, as shown in Fig. 3, simultaneouslyground. The plates 22 at the inner sides of the posts -2 and 3 arehardened wearing plates against which the end rings 'III on the arbormay contact. Because the arbor I for the small diameter rings is of asmalle-r diameter than the arbor used with the larger piston rings, thearbor bearing blocks I2 are elevated by the inter-position of a spaceror shim 23 (Fig. 4) -between the upper ends of the posts 2 and 3 and thelower sides of the blocks.

It is evident that the connection of the attachment to the machine tocondition the machine to grind the rings of small diameter is veryquickly made. Bolts are passed through the bars I into the posts 2 and3, and the blocks i2 are removed, the spacers vor shims 23 located inplace, and then the block-s I2 reconnected.

The rings are driven by the rollers f5 through the interposed idlerollers I8 at the times when said rollers 6 are moved inwardly towardeach other, and when rollers 6 are moved outwardly in the operation ofthe machine, the rollers I8 follow them by reason of the action of thespring 20, whereupon the rings on an arbor which have been ground may beremoved with the arbor, and another arbor with unprocessed rings to beground put in place of those removed, the machine operati-ng the same asdescribed in my Patf ent #2,397,298.

The attachment described has proved very practical and useful. It makesunnecessary the building of a separate complete machine for grinding therings of smaller diameters and utiy lizes machines designed and builtfor grinding rings of a .larger diameter. Not only is the expense ofbuilding separate machines avoided, but the floor space in a factory isnot increased. The

demand for the small diameter rings is increasing. Their rapid grindingat their outer curved surfaces to precise dimensions and in largequantity economical production, is thus most effectively andeconomically attained.

The invention is defined in the appended claims l l and is to beconsidered comprehensive of all forms of structure coming within theirscope.

l'. claim:

l. An attachment for ring grinding machines comprising, two spaced aparthorizontal bars located in substantially the same plane adapted to beconnected to vertical spaced arbor supporting posts, a horizonal rockshaft mounted on and extending between the ends of said bars, one ofsaid rock shafts extending between one of the ends of the spaced barsand the other between the other ends thereof, arms secured to said rockshafts adjacent their ends extending upwardly therefrom, horizontalrollers rotatably mounted at the upper ends of said arms, a resilientcover on each of said rollers, and yielding means con- 4 nected withsaid arms normally tending to move said rollers away from each other.

2. A structure as defined in claim 1, said yielding means comprisingmembers connected one to each rock shaft and extending downwardlytherefrom, and coiled spring means connecting the lower vends of Saidmembers tending "to pull said lmembers toward each other and move therollers away from each other.

3. In a machine as described, an arbor support including, spaced apartposts having recessed upper ends adapted to support the end portions of`an 'arbor from which rings may be suspended, and an attachment mountedon said posts at the inner sides thereof comprising, a horizontal bardetachably connected to each post below its upper end, each 4'bar havingends extending beyond the sides of the posts, rock shafts mounted on theend portions of said bars and extending between them, aI-ms extendingupwardly from the rock shafts, -horizontal rollers mounted 'on andextending between the upper ends of the arms adapted to bear againstopposed sides of rings on an arbor, each l'of' said Vertical postshaving a block at -its upper end w-ith a 4concave recess therein, meansfor detachably connecting said locks to the posts, and a fil-ler or shimvbetween the lower 'end of each of sa-id blocks and the upper end ofeach post detachably a-nd removably connected with its associated block`and post.

4. The elements of claim 3 in which said second rollers are movabletoward and away from said arbor and yieldable means for moving them awayfrom the arbor.

5. In a machine fas described, an farbor support including, spaced apartposts having recessed upper ends adapted to support the end portions ofan arbor from which rings m-ay be suspended, and an attachment mountedon said posts at the inner sides thereof comprising, a horizontal bardetachably connected to each post below its upper end, each bar havingends extending beyond the sides of the posts, rock shafts mounted on theend por-tions of said bars and extending between them, arms extendingupwardly from the rock shafts, horizontal rollers mounted on andextending between the upper ends of the arms adapted to bear againstopposed sides of rings on an arbor, and a member connected to each rockshaft extending downwardly therefrom, and a coiled tension springconnecting the lower ends of said members.

6. A machine of the class described comprising two spaced apartbearings, an arbor rotatably supported in said bearings and supporting aplurality of rings, a pair of rollers on opposite sides and parallelwith said arbor and movable toward and from the arbor, means forrotating said rollers and a second pair of rollers smaller in diameterthan the first rollers, extending parallel with the arbor and interposedbetween and in engagement with said rst rollers and said rings above thehorizontal centers thereof.

ROBERT STEN'VVALL.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS

